Generate points on the surface of an ellipse

This function generates points by transforming points on the surface of a sphere.

Usage

gen_vc_ellipse(vc, xm = rep(0, ncol(vc)), n = 500)

Arguments

vc

symmetric square matrix describing the variance-covariance matrix which defines the shape of the ellipse.

xm

center of the ellipse, a vector of length equal to the dimension of vc

n

number of points to generate

Value

matrix of size n x p

Examples

require(ggplot2)
require(tibble)
ell2d <- gen_vc_ellipse(vc = matrix(c(4, 2, 2, 6),
                        ncol=2, byrow=TRUE),
                        xm = c(1,1))
ell2d <- as_tibble(ell2d)
ggplot(ell2d, aes(x = V1, y = V2)) + geom_point() +
  theme(aspect.ratio=1)